Polyamide has been utilized extensively as a synthetic filament. While its structural and mechanical properties make it attractive for use in such capacities as carpeting, one major disadvantage of polyamide is that it is easily stained. Therefore, a system that would accentuate the positive mechanical and structural properties of polyamide while at the same time eliminating or decreasing the negative properties with respect to stainability, would constitute a major improvement in the art.
Composite filaments with a sheath core relationship are known in the art. U.S. Pat. No. 3,700,544 discloses a composite filament having two different components arranged in a sheath core relationship. The filaments have an improved flexural rigidity and the sheath component has a better dyeability than the core component.
U.S. Pat. No. 3,725,192 discloses a two-component filament of a sheath core type having an improved dyeability. EP-A 399,397 discloses a sheath-core bicomponent filament having antistatic properties wherein the core polymer contains carbon black.
An object of the present invention was to provide filaments with reduced stainability and high mechanical and structural properties.
Another object was a carpet with reduced stainability based on these filaments.